Nearly 30 percent of Manhattan’s properties are protected by landmark status, the report found, noting that the Upper West Side and SoHo/Greenwich Village, where a whopping 70 percent of properties are protected, have the highest household median incomes in the city.

It is more difficult to develop landmarked housing because of onerous regulations and the costs of complying with landmark standards, REBNY said, claiming that historic designation increases housing prices and concentrates wealth in the heavily landmarked areas. The report also claimed that landmarking was stifling Manhattan’s economic growth and job creation.

“Too often Historic District designation effectively prohibits the full development potential of underdeveloped sites,” the report stated, citing a proposal shot down by the Landmarks Preservation Commission to build a 10-story addition atop a five-story building surrounded by 14- and 15-story buildings. in the Upper East Side’s historic district.

There are also 48 vacant lots and 50 parking lots — representing roughly 2.6 million square feet of potential development — on landmarked properties in Manhattan, the report found.

“Essentially, the landmarks law is being used as a sword instead of a shield, as it was originally intended,” the report said.

The Landmarks Preservation Commission noted that it approved a record number of landmarks at the same time the city’s economy achieved record growth.

“The report ignores the fact that the agency has approved hundreds of new buildings and additions in historic districts as well as substantial changes to individual landmarks, and consistently strikes a balance between the city’s need to preserve its great architecture and its need to grow and evolve,” an LPC spokeswoman said.

“They are not talking about the fact that in the late ‘80s they wanted to demolish Broadway theaters,” Bankoff said of REBNY, pointing out that those theaters are now a substantial “economic engine” for the city.

“I think that evidence has shown that Manhattan is not suffering,” Bankoff added, “and that more buildings have built in the last 12 years [under Mayor Michael Bloomberg] than in the previous 10.”

Bankoff is working with at least two-dozen community groups who want to create new historic districts across the boroughs — citywide roughly 3 percent of properties are landmarked.

“People buy into historic districts because they know what they’re buying,” he said. “It protects investments.”

DNAinfo.com is New York's leading hyper-local news source, covering New York City's neighborhoods. We deliver up-to-the-minute reports on entertainment, education, politics, crime, sports, and dining. Our award-winning journalists find the stories - big or small - that matter most to New Yorkers.